Archaeological specimens

Carbon has seven isotopes. In 1961 the International Union of Pure and Applied Chemistry adopted the isotope carbon-12 as the basis for atomic weights. Carbon-14, an isotope with a half-life of 5715 years, has been widely used to date such materials as wood, archaeological specimens, etc. 

An example of a higher resolution map from the EPMA is given in Figure 5.11, where the sample is again an archaeological specimen - a pair of shears from the same site as the specimen shown in Figure 5.10. Here the weld lines are marked by lines of sulphide and slag particles in an area depleted of phosphorus. 

Figure 5.35 is an image of an archaeological specimen comprising a small fragment of a Urartian bronze belt of about the 8th 7th centuries BC. 

Clow, P. (1982), The Prevention of Bronze Disease in Archaeological Specimens, thesis, Portsmouth Polytechnic, Portsmouth. 

Peyote is a common term for two species of cactus, Lophophora williamsii and L. diffusa, native to Mexico and Texas. Archaeological specimens suggest that peyote has been used ceremonially for perhaps as many as 8,000 years. Known to the Aztecs as peyotl, the ritual use of this cactus has persisted among... 

DNA extracted from archaeological specimens, ancient DNA (aDNA), provides the researcher a window into prehistory, allowing one to say something absolute about the genetic characteristics of someone or something that lived in the past. While modem DNA studies can make predictions about the past based... 

A method for the decontamination of non-skeletal remains (e.g. coprolites and quids) has not been developed. While many researchers use ultraviolet (UV) irradiation to destroy contamination (see studies reviewed in 31, 33), no study has demonstrated that this technique is actually effective in removing contamination on archaeological specimens (33). One way to avoid potential contamination when extracting DNA from coprolites and quids is to take samples from the interior portions of the specimens. 

Another major problem associated with the extraction of DNA from archaeological specimens is that the procedure often co-extracts impurities that can later complicate, or prevent, the study of the extracted DNA by inhibiting PCR amplification (reviewed by 5). Commonly encountered inhibitory substances found in aDNA extracted from teeth, bones, mummified tissue, and coprolites include humic acids, ftilvic acids, tannins, porphyrin products, phenolic compounds, hematin, and collagen type I (37—42). The formation of Maillard products, commonly encountered in coprolite samples, can also prevent PCR amplification by causing DNA to become inaccessibly trapped in these sugar-derived condensation products (12). As the negative results in many aDNA studies are attributed to the presence of PCR inhibitors, our extraction method outlined below pays particular attention to the problem and offers a simple test for the presence of PCR inhibitors in DNA extracts. 

As mentioned above, impurities co-extracted with DNA from archaeological specimens can make the study of the DNA difficult, if not impossible. Through a... 

As illustrated by the examples above, the analysis of DNA extracted from archaeological specimens can provide unique insights about the past. However, the study of aDNA is methodologically challenging, primarily due to the problematical state of its preservation. As such, protocols developed specifically for the extraction and analysis of ancient DNA have been developed, of which we have highlighted one that we have developed over the past few years. Our protocol offers solutions to two of the most common problems associated with the study of aDNA the possible presence of contamination on the surfaces of samples and/or the co-extraction of PCR inhibitors. We are optimistic that with attention to proper aDNA protocols, data acquisition, and authentication of results, DNA extracted from archaeological specimens will continue to provide a wealth of information about the past. 

Kemp and colleagues (5) have suggested that this test is improperly conducted with a modem DNA positive control. For reasons unclear at this time, the effect of PCR inhibition on DNA is influenced by the concentration and/or quality of the DNA template. This aspect of aDNA research has been poorly explored, but a more thorough understanding of this phenomenon will likely improve our ability to study DNA extracted from archaeological specimens. 

When bone is treated with ionising radiation, free radicals are trapped in the crystal lattice of the bone (Gordy etal., 1955) and consequently can be detected by EPR spectroscopy. Prior to its application for the identification of irradiated food, the technique was used to date archaeological specimens (Ikeya and Miki, 1980) and as an in-vivo dosimeter to determine the level of human exposure to radiation (Pass and Aldrich, 1985). 

Comparison of Model Fabrics with Archaeological Specimens. To... 

The present method of analysis offers several distinct advantages. The first of these is speed calcium, barium, and strontium concentrations are determined simultaneously in a short irradiation, and analysis of up to seven samples can be completed within hours. Neutron activation analysis is highly sensitive to the elements of interest compared with other methods such as x-ray fluorescence and atomic absorption techniques. Additionally, the required sample size is small (10-20 mg), thus resulting in little alteration of archaeological specimens. 

Obtaining the Gross Sample. It is diflicult to simply assess the problem of obtaining a representative sample from an archaeological specimen. In many, if not most cases, the specific technique used must be determined on a specimen-to-specimen basis. If the entire shard cannot be used, the difliculties become compounded. 

It is applicable to a wide variety of clinical, pathologic, or forensic specimens, as well as to formalin-fixed tissne, inactivated bacterial cultnres, and archaeological specimens. However, since PCR detects nucleic acids from both living and dead microbes, this mnst be taken into account if PCR is used to monitor response to therapy. 

Merrill, WL. 1977. An Investigation of Ethnographic and Archaeological Specimens of Mescalbeans (Sophora secundiflora) in American Museums. (Technical Reports No. 6) Museum of Anthropology, University of Michigan, Ann Arbor, mi. 

X-ray fluorescence offers a number of impressive advantages. The spectra are relatively simple, so. spectral line interference is minimal. Generally, the X-ray mcthixl is nondestructive and can be used for the analysis of paintings, archaeological specimens, jewelry, coins, and other valuable objects without harm to the sample. Furthermore, analyses can be performed on samples ranging from a barely visible speck to a massive object. Other advantages include the speed and convenience of the procedure, which permit multielement analyses to be completed in a few minutes. Finally, the accuracy and precision of X-ray Huorcscence methods often equal or exceed those of other methods. ... 

Dating archaeological specimens (). Analyses of aerosol particles... 

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